Hey,
I just sort of got donated a 4x10 cabinet and a 4-rack head and want to do something with it. As I'm a poor student and currently play through a 30W solidstate laney combo, I want to build my own amp with it, but don't want to jump into the deep end...
The amp in it at the moment is a 150W mosfet poweramp and some crap solid state preamp that is a seperate module that plugs straight into the poweramp (it was being used as a bass amp). I was thinking to start with I'd just build a vavle preamp to drive the poweramp that's already in it as I don't feel condident enougth to fool around with high voltages yet, but where can I get a good layout (vero or PCB) for a valve preamp for guitar that would sound good driving the mosfet power amp and doesn't require me to tangle with death to build?
-Adam
As far as I know, even tube preamps use high voltage. I could be wrong though. There was a site about making low voltage tube amps that go up to around 1/8w, that type of power would be fine for a preamp. Don't remember the site though.
Don't be scared of voltage. Make real McTube, there's PCB project on tonepad. I started with Firefly tube amp and nothing happened. Just use common sense and you're safe.
A lot of solid state preamps involve op-amps and are therefore run at relatively low voltages compared with valve preamp stages. Bear this in mind - you don't want to blast the hell out of the power stage!
Find out what voltage the preamp is run off first, then start making decisions.
Is retaining the original solid state power amp important to you? If not, why not go all tube?
Rich at www.guytronix.com (http://www.guytronix.com) sells small wattage tube amp kits that are just wonderful. I build the 8 watt Ardmore head and did not kill myself in the process. Sounds great and at 8 watts is it easily loud enough to keep up with my drummer.
FWIW,
-dano
hrm, that real mctube preamp looks good from tonepad, that way I could get tonepad to make the PCB for me to save effort and it's only 12V.
Retaining the original poweramp is pretty important, as I'm very poor. I don't have much to spend on parts so I wanna keep the building down to a minimum. I really do want a valve-like sound tho. Plus I don't really wanna do anything high voltage yet, I will do eventually but not now.
I haven't actually got the cab/head yet as I should be getting it sometime next week, as soon as I do I'll check out exactly how it works and post some images of it. It's a custom-built amp tho (my friend built it, he's giving it away coz he's moving country and can't take it with him).
-Adam
Jaycar electronics has a tube preamp kit which has its own power supply which you buid. it steps the power up from 12 v i think
McTube isn't 12V. I mean, you can make it to work with 12V DC input, but you need one more transformer inside that will give 120V back...